Purim Legalities
Question #1: Achashverosh complies with Esther's request to
undo his decree by issuing a new decree authorizing the Jews
to defend themselves. This is peculiar, as one would expect
him to simply nullify the old decree. A legislative body has
the power to revoke its own legislation.
Question #2: How is Achashveroshe's institution of a new tax
relevant to the story of the Megillah and therefore worthy of
recounting.
Question #3: Why did Achashverosh kill the sons of Haman?
What did they ever do to him?
Question #4: Once Achashverosh was killing off Haman's family,
why did he not kill Haman's wife Zeresh?
The Big Answer:
In the case at hand, Achashverosh could not revoke his own
decree because he had a contract with Haman, for which Haman
paid consideration of 10,000 pieces of silver. So Achashverosh
was not free to simply revoke the decree that he had made.
Even a contract can be "breached", though, if one is willing
to pay. So why did Achashverosh not revoke his decree and pay
back the contract. Achashverosh must not have been able to
afford paying off the contract. He was hard up for cash as
evinced in his soon instituting a new tax. (He had to pay for
that party after all, and Midrashic sources say he owed his
kingship in the first place to wealth.) In addition, breach
may have resulted in his having to pay damages of "expectation",
which would amount to all the wealth people had expected to
plunder from the Jews. This would be a fairly large amount
which he certainly would not want to pay.
However, even if he did not expressly violate the terms of the
contract, he seemingly violated its spirit and was therefore
perhaps guilty of "constructive breach". This is probably why
he killed all of Haman's sons; this way there would be no one
to sue on behalf of his estate. He did not kill Haman's wife
Zeresh, because women in Ancient Persia did not have property
rights and she therefore would not have "standing" to sue on
behalf of the estate.
But could all the people who expected to plunder the Jews sue
for constructive breach? The answer is no - because they were
"third party beneficiaries" to the contract and therefore had
no "privity" to sue. In addition, just in case they could
construct privity to sue, Achashverosh instituted the tax to
show then whatever the general populace might try to sue him
for in a "class action" he could take right back in a general tax.
Res Ipsa Loquitur V'Hamevin Yovin